Biogeography of Juan-Fernandez Endemic Grasses resolved as sister to Megalachne. Bayesian divergence dating and dispersal-extinctioncladogenesis range evolution analyses estimated the split of the Fernandezian clade from its ancestral southern American Pampas-Ventanian Loliinae lineage in the Miocene-Pliocene transition, following a long distance dispersal from the continent to the uplifted volcanic palaeo-island of Santa Clara-Masatierra. Consecutive Pliocene-Pleistocene splits and a Masatierra-to-Masafuera dispersal paved the way for in situ speciation of Podophorus and Megalachne taxa.

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Many studies have tried to assess the role of both deterministic and stochastic processes in community assembly, yet a lack of consensus exists on which processes are more prevalent and at which spatial scales they operate. To shed light on this issue, we tested two nonmutually exclusive, scale‐dependent hypotheses: (1) that competitive exclusion dominates at small spatial scales; and (2) that environmental filtering does so at larger ones. To accomplish this, we studied the functional patterns of tropical montane forest communities along two altitudinal gradients, in Ecuador and Peru, using floristic and functional data from 60 plots of 0.1 ha. We found no evidence of either functional overdispersion or clustering at small spatial scales, but we did find functional clustering at larger ones. The observed pattern of clustering, consistent with an environmental filtering process, was more evident when maximizing the environmental differences among any pair of plots. To strengthen the link between the observed community functional pattern and the underlying process of environmental filtering, we explored differences in the climatic preferences of the most abundant species found at lower and higher elevations and examined whether their abundances shifted along the elevation gradient. We found (1) that greater community functional differences (observed between lower and upper tropical montane forest assemblies) were mostly the result of strong climatic preferences, maintained across the Neotropics; and (2) that the abundances of such species shifted along the elevational gradient. Our findings support the conclusion that, at large spatial scales, environmental filtering is the overriding mechanism for community assembly, because the pattern of functional clustering was linked to species’ similarities in their climatic preferences, which ultimately resulted in shifts in species abundances along the gradient. However, there was no evidence of competitive exclusion at more homogeneous, smaller spatial scales, where plant species effectively compete for resources.

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We introduce the FunAndes database, a compilation of functional trait data for the Andean flora spanning six countries. FunAndes contains data on 24 traits across 2,694 taxa, for a total of 105,466 entries. The database features plant-morphological attributes including growth form, and leaf, stem, and wood traits measured at the species or individual level, together with geographic metadata (i.e., coordinates and elevation). FunAndes follows the field names, trait descriptions and units of measurement of the TRY database. It is currently available in open access in the FIGSHARE data repository, and will be part of TRY’s next release. Open access trait data from Andean plants will contribute to ecological research in the region, the most species rich terrestrial biodiversity hotspot.

En este trabajo se presenta el listado florístico, incluyendo las formas de vida de las angiospermas presentes en las sabanas de San Miguel Allende (Campeche) y de Chacho Lugo (Yucatán). Se registraron 142 especies pertenecientes a 96 géneros y 36 familias, siendo las plantas herbáceas las que tienen la forma de vida dominante. El valor Ij obtenido fue de 0.169, lo que demuestra las notables diferencias en la composición florística de cada una de las sabanas, las cuales comparten sólo 24 de las 142 especies registradas. Las características geomorfológicas de cada lugar indican variaciones en la dinámica hidrológica, lo que se refleja en notables variaciones en la composición florística. Así, San Miguel Allende se clasifica como una sabana estacional, caracterizada por la presencia de géneros como Trachypogon y por la escasa presencia de representantes de la familia Cyperaceae; mientras que Chacho Lugo se clasifica como una sabana hiperestacional, donde abundan especies típicas de ambientes más húmedos (Cyperaceae, Eriocaulaceae y Lentibulariaceae). La presencia de endemismos como Echeandia campechiana, E. petenensis y Hampea trilobata, así como la baja presencia de plantas introducidas, muestran la importancia florística y ecológica de estos enclaves tan pobremente estudiados y afectados por las actividades antropogénicas.

Centaurea stuessyi is described as new to science from the eastern Iberian Peninsula, Spain. The range of this new species coincides with the zone of overlap of the ranges of two related species, C. antennata (subsp. antennata) and C. linifolia. The chromosome number found in the new species (2n = 44) reinforces its differences from C. linifolia (2n = 22) and C. antennata (2n = 22). The new species is compared with related species, and a description is given of its ecological preferences.